The Mountain Geohazard Assessment Model MoGAM

Transcription

1 Taj Haz Remote Geohazards Assessment in Tajikistan The Mountain Geohazard Assessment Model MoGAM Presented by Ingrid Kleinbauer University of Natural Resources and Applied Life Sciences, Vienna 1

2 Mountain Geohazard Assessment Model Content of the presentation Hazard assessment at the regional scale > Data acquisition and preparation > Change detection > Survey planning Direct survey of potential hazardous areas > Helicopter survey > Field work Hazard assessment at the local scale > Model calculations > Hazard indication rating Mo GAM Mountain Geohazard Assessment Model BOKU University, Vienna FOCUS Humanitarian Assistance 2

3 Regional scale assessment Workflow Determination of study areas Data Acquisition and Preparation and Screening Topographic Analysis Multi-Temporal: Automated Image Analysis Multi-Temporal: Manual/visual Image Analysis Extraction of information from Geological maps Change detection Selection of areas for helicopter survey 3

4 Determination of Study areas Overview of study areas Zarafshan Jirgital GBAO Elevation and relief SRTM / Borders and towns 4

5 Data Acquisition and Preparation Satellite imagery Time series > Scenes should cover each study area > Appropriate resolution (spectral and spatial) > Cloud CORONA cover should be Landsat as low TM as possible > Season/month when image is taken > Not to ignore: costs Landsat ETM ASTER

6 Data Acquisition and Preparation Elevation data > Resolution (at least 60-90m) > Quality: no gaps in the data > Accuracy > Not to ignore: costs Filled SRTM from 6

7 Scale: 1:50,000 Data Acquisition and Preparation Sovjet Topographic maps: Georeferenced, mosaicked, andscale: 1:100,000 transformedexample1:100,

8 These lakes do not exist Detecting lakes Example Rivakkul Rivakkul surroundings 2002 Automated extraction Visual interpretation 8

9 Preliminary field maps 9

10 Direct survey Helicopter 10

11 Direct survey - Field work Field work > Field trips lasting one to several days > by car or by helicopter drop off > Equipment: satellite telephone, field maps, GPS receiver, field computer, field book, camera, sample bags > Features of interest: slopes, dams, landslide deposits, valley bottom, (rock) glacier > Integration of new information and structured storage of data 11

12 Direct survey - Field work Field work Upper Bartang Valley Gunt Valley Rivakkul Varshedzdara Wakhan Corridor 12

13 Model calculations 13

14 Model calculation - Example FLO 2D and RAMMS 14

15 Hazard indication rating Post-Assessment Hazard Rating Code Intensity I II III IV Class Low intensity Medium intensity High intensity Very high intensity Probability Code Class 0 Zero probability 1 Low probability 2 Medium probability 3 High probability 4 Very high probability Code 6 Very high Confidence Code 5 4A 3B C 2 D 1 E Hazard indication rating hazard Class High hazard Range of s <25 Very Medium high hazard confidence 15 <20 High Moderate confidence 10 <15 hazard Medium confidence Low hazard 5 <10 Low confidence Very low 0 <5 No hazard knowledge Village Probability as function of intensity I II III IV Confidence B Rating 20 15

16 Hazard indication maps - legend 16

17 Hazard indication map - example Hazard Indication Map 17

18 Thanks for your attention! Discussion 18